This invention relates to a card connector for use in a various kinds of electric or electronic appliances such as printers and card readers, and more particularly to a card connector having a reliable detecting mechanism when a card is inserted and removed into and from the connector.
There have been many kinds of cards as media for a variety of information. It has been a common practice to obtain or accumulate various information from or onto a card which is adapted to be inserted into a card connector connected to an information appliance.
In using a card in such a manner, it is required to insert the card into a card connector with great certainty. Therefore, there is a need to ascertain whether the card has been completely inserted or not. For this purpose switching mechanisms are frequently used.
There have been switching mechanisms for detecting an inserted card into a connector by displacement of one element in a thickness direction (Patent Literature 1), a width direction (Patent Literature 2) or an inserting direction of the connector.
The mechanism for detecting by the displacement of the element in the inserting direction will be explained with FIGS. 5A and 5B. FIG. 5A is a view for explaining a state of switching terminals before inserting a card, while FIG. 5B is a view for explaining a state of the switching terminals when a card has been inserted. As shown in FIGS. 5A and 5B, the card connector 60 of the prior art mainly comprises a housing 62, contacts, and two switching terminals 66 and 68. Prior to the insertion of a card, the two switching terminals 66 and 68 are separated from each other. Upon insertion of a card, first the card will contact the first switching terminals 66 viewed on the lower side in the drawing. On proceeding of the insertion, the first switching terminal 66 moves in the inserting direction of the card (in the upward direction viewed in the drawing) so that the first switching terminal 66 is brought into contact with the second switching terminal 68, thereby detecting the fact that the card has been inserted in the connector.
Japanese Patent Application Opened No. H10-320,511/1998 (Patent Literature 1) discloses a card reader capable of detecting an inserted card by displacement of a switching element in a thickness direction. This card reader has a thin card case so as to obtain a suitable elastic displacement of a switching element and an appropriate contacting force by a slight force for inserting a card into the card reader, thereby achieving good wiping effect and contact caused by pressurized contact and deformation of first and second following switching elements. A card distal end detecting device comprises first and second following switch elements 1 and 2 whose first and second elastic contact pieces 5 and 6 extend along the surface of a memory card and are arranged opposite to the card in its thickness. The first elastic contact piece 5 is so arranged that after an electrode pad arranged on the surface of the inserted card begins to contact the contacts arranged in the card reader, the first elastic contact piece 5 is elastically displaced in the thickness direction of the card by an urging force of the front edge of the card and comes into contact with the second elastic contact piece 6. The second elastic contact piece 6 is so arranged that it is elastically displaced in the thickness direction of the card by an urging force by the first elastic contact piece 5 to perform wiping at the pressurized contact portion.
Japanese Patent Application Opened No. 2001-351,709 (Patent Literature 2) discloses a connector capable of detecting an inserted card by displacement of a switching element in a width direction. This invention has an object to provide a connector into which a plurality of memory cards different in thicknesses can be selectively inserted in order to operate information appliances. The connector includes a connector main body consisting of a rear wall and side walls formed along their full length with receiving portions conforming to side edges of memory cards to be used, card identification terminals in a plurality of rows on the inner surface of one side wall, terminals provided on the rear wall for writing the electronic information and reading the accumulated information onto and from the cards, and protection terminals provided at appropriate positions on the other side wall for prohibiting writing. The card identification terminals are made from a spring-like metal strip piece and arranged in a plurality of rows on the side wall, while identification tabs are arranged on the side wall to separate from the card identification terminals when a card is not inserted. When the identification tabs contact the card identification terminals, the existence of the card is identified.
In recent years, with the miniaturization of the information appliances as well as boards or substrates used therein, surface areas of the boards to be utilized have become extremely narrower. Such a limitation of the surface area of the board leads to the use of a plurality of boards. On the other hand, if a plurality of connectors are required for exchanging a plurality of memory cards, information appliances would become bulky which would be inconvenient for carrying them.
The proposals for detecting the insertion of a card are described above. With the switching mechanisms disclosed in the Patent Literatures 1 and 2, however, there would be clearances between a card and a card fitting opening of a connector. Therefore, if the card is inserted into the fitting opening in a state that one edge of the card on the side of the switch is closer to the side wall of the fitting opening than the other edge to the other side wall, then the insertion of the card would be prematurely identified prior to the complete insertion of the card. For the purpose of overcoming this problem, if the clearance between the card and the fitting opening is made as little as possible, the fabrication cost would go up, and the insertion of a card would become difficult.
With the connector which detects a card by the displacement of the switching terminal in the inserting direction of the card as shown in FIGS. 5A and 5B described above, moreover, in the case of a thinner card, the reaction force of the switching terminal would become larger so that the removing force for the card would not fulfil the removing force prescribed in the Standard of card, that is, normally more than 1N (98 g).